iCub::ctrl::minJerkTrajGen Class Reference

Generator of approximately minimum jerk trajectories. More...

#include <minJerkCtrl.h>

Inheritance diagram for iCub::ctrl::minJerkTrajGen:

Public Member Functions
	minJerkTrajGen (const unsigned int _dim, const double _Ts, const double _T)
	Constructor.
	minJerkTrajGen (const yarp::sig::Vector &y0, const double _Ts, const double _T)
	Constructor with initial value.
	minJerkTrajGen (const minJerkTrajGen &z)
	Copy constructor.
minJerkTrajGen &	operator= (const minJerkTrajGen &z)
	Assignment operator.
void	computeNextValues (const yarp::sig::Vector &yd)
	Compute the next position, velocity and acceleration.
Public Member Functions inherited from iCub::ctrl::minJerkBaseGen
	minJerkBaseGen (const unsigned int _dim, const double _Ts, const double _T)
	Constructor.
	minJerkBaseGen (const yarp::sig::Vector &y0, const double _Ts, const double _T)
	Constructor with initial value.
	minJerkBaseGen (const minJerkBaseGen &z)
	Copy constructor.
minJerkBaseGen &	operator= (const minJerkBaseGen &z)
	Assignment operator.
virtual	~minJerkBaseGen ()
	Destructor.
virtual void	init (const yarp::sig::Vector &y0)
	Initialize the trajectory.
const yarp::sig::Vector &	getPos () const
	Get the current position.
const yarp::sig::Vector &	getVel () const
	Get the current velocity.
const yarp::sig::Vector &	getAcc () const
	Get the current acceleration.
double	getT () const
	Get the trajectory reference time in seconds (90% of steady-state value in t=_T, transient extinguished for t>=1.5*_T).
double	getTs () const
	Get the sample time in seconds.
bool	setT (const double _T)
	Set the trajectory reference time (90% of steady-state value in t=_T, transient extinguished for t>=1.5*_T).
bool	setTs (const double _Ts)
	Set the sample time.

Protected Member Functions
virtual void	computeCoeffs ()

Additional Inherited Members
Protected Attributes inherited from iCub::ctrl::minJerkBaseGen
Filter *	posFilter
Filter *	velFilter
Filter *	accFilter
yarp::sig::Vector	pos
yarp::sig::Vector	vel
yarp::sig::Vector	acc
yarp::sig::Vector	lastRef
double	Ts
double	T
unsigned int	dim

Detailed Description

Generator of approximately minimum jerk trajectories.

The min jerk trajectory is approximated using a 3rd order LTI dynamical system (for more details see Pattacini2010). Position, velocity and acceleration trajectories are computed. The main advantage with respect to the standard polynomial form is that if the reference value yd changes there is no need to recompute the filter coefficients.

Definition at line 351 of file minJerkCtrl.h.

Constructor & Destructor Documentation

minJerkTrajGen() [1/3]

minJerkTrajGen::minJerkTrajGen	(	const unsigned int	_dim,
		const double	_Ts,
		const double	_T
	)

Constructor.

Parameters

_dim	number of variables.
_Ts	sample time in seconds.
_T	trajectory reference time (90% of steady-state value in t=_T, transient extinguished for t>=1.5*_T).

Definition at line 374 of file minJerkCtrl.cpp.

minJerkTrajGen() [2/3]

iCub::ctrl::minJerkTrajGen::minJerkTrajGen	(	const yarp::sig::Vector &	y0,
		const double	_Ts,
		const double	_T
	)

Constructor with initial value.

Parameters

_y0	initial value of the trajectory.
_Ts	sample time in seconds.
_T	trajectory reference time (90% of steady-state value in t=_T, transient extinguished for t>=1.5*_T).

minJerkTrajGen() [3/3]

minJerkTrajGen::minJerkTrajGen

(

const minJerkTrajGen &

z

)

Copy constructor.

Parameters

z	the object to copy.

Note

After copy, internal filters are reset.

Definition at line 390 of file minJerkCtrl.cpp.

Member Function Documentation

computeCoeffs()

void minJerkTrajGen::computeCoeffs ( )

protectedvirtual

Implements iCub::ctrl::minJerkBaseGen.

Definition at line 407 of file minJerkCtrl.cpp.

computeNextValues()

void minJerkTrajGen::computeNextValues ( const yarp::sig::Vector &  yd )

virtual

Compute the next position, velocity and acceleration.

Parameters

yd	desired final value of the trajectory.

Implements iCub::ctrl::minJerkBaseGen.

Definition at line 447 of file minJerkCtrl.cpp.

operator=()

minJerkTrajGen & minJerkTrajGen::operator=

(

const minJerkTrajGen &

z

)

Assignment operator.

Parameters

z	the object to copy.

Note

After copy, internal filters are reset.

Definition at line 398 of file minJerkCtrl.cpp.

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The documentation for this class was generated from the following files:

• icub-main/src/libraries/ctrlLib/include/iCub/ctrl/minJerkCtrl.h
• icub-main/src/libraries/ctrlLib/src/minJerkCtrl.cpp